Flexible mount incandescent electric lamp



Ap 1941- A. L POWELL 2,238,598

FLEXIBLE MOUNT INCANDESCENT ELECTRIC LAMP Filed Dec. 1, 1939 INVENTOR A.5. WW!

r/UJJ W W L ATTORNEY v Patented Apr. 15, .1941

FLEXIBLE MOUNT INCANDESCENT ELECTRIC LAMP Arthur Lester Powell, PrinceBay, Staten Island, N. Y., assignor to Westinghouse Electric 8;Manufacturing Company, East Pittsburgh, Pa., a corporation ofPennsylvania Application December 1, 1939, Serial No. 307,036

14 Claims.

This invention relates to incandescent electric lamps, and moreparticularly to one small enough in size and having a mount sutllcientlyflexible, whereby it is especially adapted for use as a locomotiveheadlight, or for a similar rpose.

The principal object of my invention, generally considered, is toprovide a rough service lamp having a flexible mount and with a lightcenter length sufilcientlyshort to adapt it for use as a locomotiveheadlight.

Another object of my invention is the provision of a flexible mountlamp, in which the filament-supporting leads are elongated and bent backon themselves, whereby the desired flexibility is obtained withoutincrease in bulb length, and the arbor end portion or insulatorisseparated from the stem in order to allow the filament and associatedparts to vibrate in unison.

A further object of my invention is the provision of a lamp in which allparts of the filament and those parts directly connected thereto, areadapted to vibrate in unison and thereby avoid any tearing or shakingaction on the filament, making it possible to use the weaker nonsag wirefor said filament, rather than the usual wire not immunized against sag.

A still further object of my invention is the provision of a flexiblemount incandescent electric lamp in which varying vibrations, ofseparate but connected parts, are eliminated by connecting an insulatorbetween supporting leads by wires inserted therein and wrapped aroundand/or spot-welded to said leads for supporting said insulator, wherebysaid filament vibrates in synchronism with its supporting means and thelead tips.

Other objects and advantages of the invention, relating to theparticular arrangement 'and construction oi. the various parts, willbecome apparent as the description proceeds.

Referring to the drawing illustrating my invention:

Figure ,1 is an elevational view of a lamp embodying my invention, withpart of the envelope broken away to more clearly illustrate the interiorconstruction.

Figure 2 is an elevational view of the lamp of Figure 1, from the right.

Figure 3 is a detailed view of the supporting lead end portions andconnected button or insulating member.

Figure 4 is a view corresponding to Figure 2, but showing only the pressand mount of a modifled form of lamp embodying my invention.

Figure 5 is an elevational view of the mount of Figure 4, from the left.

Figure 6 is a fragmentary view corresponding to Figure 5, but showinganother embodiment of my invention.

Figure 7 is a sectional view on the line VII- VII of Figure 6, in thedirection of the arrows.

It has been the practice to make lamps suitable for locomotiveheadlights with the filament supported directly from the arbor button,and the leads extending from a press and with their end portionsconnected to the ends of the tungsten filament. With such a constructionany shock or vibration of the lamp is transmitted directly to thefilament. Such a filament having a natural period of vibration differentfrom that of the rest of the mount, is whipped around considerably,making it necessary to use tungsten wire not treated against sag, asnon-sag tungsten wire is not strong enough for such service. Because thewire used was of the sag type, the coiled turns opened up, causingdistortion of the filament to the extent that the coils were apt toshort circuit, on one another or the supports, causing burn-outs. Suchdistortion also caused a poor beam and poor lumen maintenance.

In accordance with my invention I propose a construction whicheliminates varying vibrations of separate parts, and allows thefilament, supports, and lead tips, to vibrate together in synchronism.The leads are shaped so as to act as a shock absorber, minimizin thevibration actually transmitted to the lead tips. The construction alsoreduces the vibration of the filament to such an extent that non-sag or8 wire may be used for the filament, rather than B wire, or such thathas not been treated against sag. In this way I am enabled to get a muchbetter beam and lumen maintenance than when using sag wire.

Referring to the drawing in detail, and first considering the embodimentof my invention illustrated in Figures 1 and 2, there is shown a lamp Iiwith a relatively short light center length, and comprising a bulb orenvelope l2 having a flare tube l3' integral therewith and forming are-entrant portion terminatin in a press I 4. The lamp of the presentembodiment is shown provided with a medium screw base l5.

Extending through the press are leads l6 and I1, said leads beingdesirably of nickel, nickeliron alloy, or the like, elongated, toprovide for a shockproof or flexible mount construction, and looped backon themselves, as indicated at l8, beyond the point of emergence fromthe press It,

in order to keep the length of the lamp short, and are then continued onto terminate in the angular end portions l9 and 2|.

. Instead of having the filament directly supported from an arbor, Iprovide what might be termed a "fioating glass insulator 22, which maybe in the form of an arbor button or end portion, as illustrated. Thisinsulator is shown anchored to the leads, between the looped portion 18and the angular portions I9 and 2|, by means of wires 23, 24, 25, and26, which are desirably formed of molybdenum or tungsten, eachpreferably having an end embedded in the insulator 22 extendinggenerally transverse to the axis of the envelope, and with the other endwrapped around, and/or spotwelded to a lead I or H. In other words, thewires 23 and 25 are desirably secured to the lead It, and the wires 24and 26 are desirably secured to the lead l1, thereby providing a strongbrace or fourlegged connection between the insulator 22 and said leads.

The coiled tungsten filament 21 desirably has ends respectivelyconnected to the free ends of the angular portions l3 and 2| of theleads, as by crimping or spot welding, and the intermediate portion isdraped over preferably alternately long and short filament support wires28, 29, 3|, 32 and 33, desirably formed of tungsten, and directedgenerally parallel to or along the axis of the envelope l2, as byextending back and forth through looped or hooked end portions of saidwires, as illustrated. The support wires desirably having their lower orfixed ends embedded in the insulator 22. It will be seen that by virtueof this construction, the insulator 22, the connected portions of theleads l6 and I1, and the supporting filament, all vibrate as a unit andare emply protected from shocks on account of the flexibility providedby the unusual length of the leads l6 and I1, and the fact that there isno relatively rigid connection between the insulator 22 and the pressl4.

In the embodiment of my invention illustrated in Figure 3, aconstruction similar to that of Figures 1 and 2, as illustrated, exceptthat the braces between the glass insulator or arbor button member 22and the preferably nickel leads i6 are in the form of relatively heavywires 23 and 25' of nickel orthe like, the lead-adjacent ends of whichare spot welded to the leads with the other ends united to molybdenum ortungsten spuds 34 and 35, extending from said insulator 22, as by beingcrimped over looped ends thereof, as illustrated. 7

Referring now to the the embodiment of my invention illustrated inFigures 4 and 5, a construction is there shown similar to that ofFigures 1 and 2, except that the preferably nickel leads I6 and I'lafter being looped to below the points 01'- emergence from thesupporting press II, as indicated at I8", are bent back to directlyoverlie said press, as indicated at 36, and are there connected by aninsulator 22'', desirably in the form of a short piece of cane glass, bymeans of spuds 31 and 38, desirably formed of molybdenum or tungsten,embedded in said insulator, and with their other ends spot-welded orotherwise secured to the leads l6 and II as shown most clearly in Figure4.

The tungsten filament 21 in the present instance, is desirably formed astwo rather than three loops, the ends thereof being desirably connectedto the angular portions I! and 2| of the leads a s in F gures 1 and 2, ad

the intermediate portions draped over supportmost clearly in Figure 4,.

Referring now to the embodiment of my invention illustrated in Figures 6and '7, there is shown a construction similar to that oflFigures 1 and2, except that the insulator 22, formed of glass, lava, or the like, isshown in the form of a U with its ends directly connected to thepreferably nickel leads l6 and II, as by fusing or clamping thereon, asillustrated. From said insulator 22" extend tungsten filament supports28, 28*, 3, 32 and 33,as in Figures 1 and 2, the incandescible ortungsten filament 21 being draped thereover, and with its ends connectedto the angular portions 2l of said leads.

From the foregoing, it will be seen that I have improved on theconstruction of lamps especially adapted for locomotive headlights byprotecting the filament against shock, and making it so that saidfilament vibrates in unison with the connected parts, thereby avoidingwhipping and tearing strains and making it possible to use a weakernon-sag or 5 wire, whereby the adber, and an incandescible filament withits ends connected to said leads and draped back and forth over saidwires.

2. A flexible mount lamp comprising a vitreous envelope provided with apress, a pair of leads elongated for flexibility, extending from saidpress and looped back on themselves to avoid unnecessary lengthening ofthe bulb, an insulating member mounted between end portions of saidleads, a plurality of wires extending from said member, and anincandescible filament with its ends connected to said leads-and drapedover said wires.

3. A flexible mount lamp comprising a glass envelope provided with apress, a pair of supporting leads extending from said press, said leadsbeing elongated, and looped back on themselves to beyond their point ofemergence from said press, in order to increase the flexibility thereof,and'provide for all parts of the filament and associated membersvibrating in unison, to

'relieve said filament of any tearing or shaking pair of bracing wiresextending generally transverse to the axis of said envelope from saidmember to each lead for holding it in position with respect thereto, aplurality of wires with j their ends embedded in said member andextending generally axial to said envelope,- and a tungsten filamentextending from the end of one of said spuds, a plurality of wires withtheir ends embedded in said member and extending generally axial to saidenvelope, and a tungsten filament extending from the end of one lead tothat of the other and draped over said wires.

6. A flexible mount lamp comprising a vitreous envelope providedwith apress, a pair of sup-- porting leads extending from said press, aninsulator separated from said press, disposed between said leads andhaving spuds extending from opposite ends and each connected to a lead,a plurality of wires extending from said member at an angle to saidspuds. and a tungsten fllament draped thereover and with its endsconneeted to said leads.

7. A flexible mount lamp comprising a vitreous envelope provided with apress, a pair of supporting leads extending from said press, aninsulating U -shaped member with its ends secured to said leads andhaving wires extending at an angle to its plane from an intermediateportion thereof, and a tungsten filament extending between said leadsand with intermediate portions supported by said wires.

8. A flexible mount comprising a press, a pair of supporting leadsextending from said press, an insulating member separated from saidpress and braced to said leads. a plurality of alternately long andshort wires extending from said member, and an incandescible filamentwith its ends connected to said leads and draped back and forth overlooped end portions of said wires.

9. A flexible mount comprising a press, a pair of supporting leadsextending from said press, said leads being elongated, and looped backon themselves to beyond their point of emergence from said press, inorder to increase the flexibility thereof, and provide for all parts ofthe filament and associated members vibrating in unison, to relieve saidfilament of any tearing or shaking action, an insulating member mountedbetween the free endportions of said leads, a plurality of wiresextending from said member, and a tungsten filament draped over saidwires and with its ends connected to said leads.

10. A flexible mount comprising a press, a pair of supporting elongatedleads extending from said press and looped back on themselves, aninsulating member, a pair of bracing wires extending from said membergenerally transverse to each lead for holding it in position withrespect thereto, a plurality of wires with their ends embedded in saidmember and extending longitudinally of said leads, and a tungstenfilament extending from the end of one lead to that of the other anddraped over said wires.

11. A flexible mount comprising a press, a pair of elongated supportingleads extending from said press and looped back on themselves, aninsulating member having spuds with looped free end portions extendingtowards said leads, and bracing wires welded to said leads and withtheir free ends crimped to the looped end portions of said spuds.

12. A flexible mount comprising a press, a pair of supporting leadsextending from said press and looped back on themselves, an insulatordisposed between said leads and having spuds extending from oppositeends and each connected to a lead, a plurality of wires extending fromsaid member at an angle to said spuds, and a tungsten filament drapedthereover and with its ends connected to said leads.

13. A flexible mount comprising a-press, a pair of supporting leadsextending from said press,

an insulating U-shaped member with its ends secured to said leads andhaving wires extending at an angle to its plane from an intermediateportion thereof, and a tungsten filament extending between said leadsand with intermediate portions supported by said wires.

14. A flexible mount lamp comprising a vitreous envelope provided with apair 01' leads elongated for flexibflity and looped back on themselves,an insulating member mounted between portions of said leads, supportingmeans extending from said member, and an imandesciblo filament with itsends connected to said leads, and an intermediate portion held on saidsupporting means.

' ARTHUR LESTER POWELL.

